Add test coverage reporting to CI (#39)

- Update CI workflow to generate coverage profile with go test
- Upload coverage data to Codecov for tracking
- Add CI status and coverage badges to README

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: justinabrahms

.github/workflows/ci.yml

@@ -26,8 +26,15 @@ jobs:
       - name: Build
         run: go build -v ./...
 
-      - name: Test
-        run: go test -race -v ./...
+      - name: Test with coverage
+        run: go test -race -coverprofile=coverage.out -covermode=atomic ./...
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v4
+        with:
+          files: ./coverage.out
+          fail_ci_if_error: false
+          verbose: true
 
   lint:
     runs-on: ubuntu-latest

README.md

@@ -1,5 +1,8 @@
 # gitstreams
 
+[![CI](https://github.com/justinabrahms/gitstreams/actions/workflows/ci.yml/badge.svg)](https://github.com/justinabrahms/gitstreams/actions/workflows/ci.yml)
+[![codecov](https://codecov.io/gh/justinabrahms/gitstreams/graph/badge.svg)](https://codecov.io/gh/justinabrahms/gitstreams)
+
 Track what your GitHub social network has been up to. Get desktop notifications
 and a rich HTML report showing repos starred, new projects, and activity from
 developers you follow.